1. Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
2. Department of EMF Research Team, Radio and Broadcasting Technology Laboratory, Electronics and Telecommunications Research Institute (ETRI), Daejon, 305-700, Republic of Korea
3. School of Electrical and Computer Engineering, Chungbuk National University, Cheongju, Chungbuk, 362-763, Republic of Korea